Over a period of only about thirty years, computers have revolutionized vast areas of human endeavor. Computers can in seconds make computations that would have taken months or years to perform using mechanical calculators. Computers are now used almost universally for word-processing in the creation of information. Hug computer data bases are readily accessible by telephone modems for dissemination of information. Computer-controlled machines can perform numerous manufacturing operations more rapidly, reliably and accurately than their human-controlled predecessors. Exploration of space would not be possible without computers for controlling the complex systems of spacecraft. The benefits of computers to mankind are incalculable.
Present-day computers require extensive intervention of human operators at some point. The primary way of communicating with a computer is by the use of a keyboard. Programs have to be keyed in when they are created. Many forms of data are keyed in for processing. The creation of verbal material using a computer as a word-processor is a totally manual operation. Along with the vast benefits of computers has come, unfortunately, an increasingly serious problem encountered by many computer operators, a problem known as repetitive stress injury ("RSI"). Operating a keyboard requires repetitive flexing of the fingers. The tendons that flex the fingers and the median nerve pass through the carpel tunnel, which is a bundle of bones and ligaments. The synovial sheaths of the ligaments may become swollen as a result of overuse and can put pressure on the median nerve, which causes numbness and tingling of the arm and hand. Sitting at a keyboard for long periods of time, with the torso, arms and hands in the same position, puts considerable stress on the muscles and tendons of the back, shoulders, and arms. The stresses can be great enough to be debilitating, often requiring the victim to wear braces or splints. Sometimes, the stresses cause damage to muscles, tendons and other tissue of sufficient severity to require surgery. In addition the pain and suffering of those afflicted with the various forms of RSI, considerable economic losses result from employee absence and reduced productivity.